| Trigger | Natural | Remote Trigger | 0 |
| Avalanche Type | Unknown | Aspect | Unknown |
| Elevation | unknown | Slope Angle | unknown |
| Crown Depth | unknown | Width | unknown |
| Vertical Run | unknown |
Avalanche: Summit
Location: Fresno
APU Snow Science 1 toured on Fresno to check out the spring snowpack. We made it to 2500′ without getting soaked.
Avalanche Details
Several natural D2-3 avalanches observed from the road along Seward Hwy (i.e. Orca, Whiteline), Portage (i.e. Door 1) and Turnagain Pass. Since none of us had been in the zone for two weeks, it was hard to define if the avalanches had happened in the last 24 hours or prior during the extended storm cycle.
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | Yes |
| Cracking (Shooting cracks)? | No |
Observer Comments
Observed several significant whumpfs both at lower elevation as well as at 2500'.
Weather
Temps above freezing the whole day.
Calm winds lower down, light breeze from E near the ridgeline.
Obscured/overcast sky.
Intermittent light rain at lower elevation and snow flurries above 2000'.
Snow surface
Unsupported moist and isothermal snowpack at lower elevation. Boot pen to crotch & ski pen 10-50cm.
At 2000' transitioned to improved skinning/skiing conditions.
Mid-elevation:~3cm 1F meltfreeze crust below 1-5cm of new snow.
Small roller balls observed above 2000'.
Snowpack
Moist and isothermal snowpack at lower elevation. Snowpack is percolating all the way to the ground. Ski conditions were catchy and challenging at the lower elevation.
--
Dug a pit and did a percolation test on ENE aspect close to the ridgeline (2500') in the trees on 20-25* slope.
HS 100-135cm.
We found a reactive layer 35 cm down, moist facets buried on March 8. This layer took a bit of force to fail, but it had lot of propagation propensity (ECTP21 & ECTP24). We also had the basal facets fail on CT 26 SC.
Rollerballs above 2000' near the rain/snowline within the last 24 hours.
We played with Koolaid tests to find out how the snowpack is draining the precipitation. Percolation is working well at the upper elevation
Flat light and snow flurries. We found relatively "dry" conditions at Summit zone considering the conditions in Girdwood, Portage and Turnagain Pass.